perf tools: Improve call graph documents and help messages

The --call-graph option is complex so we should provide better guide for
users.  Also change help message to be consistent with config option
names.  Now perf top will show help like below:

  $ perf top --call-graph
    Error: option `call-graph' requires a value

   Usage: perf top [<options>]

      --call-graph <record_mode[,record_size],print_type,threshold[,print_limit],order,sort_key[,branch]>
           setup and enables call-graph (stack chain/backtrace):

		record_mode:	call graph recording mode (fp|dwarf|lbr)
		record_size:	if record_mode is 'dwarf', max size of stack recording (<bytes>)
				default: 8192 (bytes)
		print_type:	call graph printing style (graph|flat|fractal|none)
		threshold:	minimum call graph inclusion threshold (<percent>)
		print_limit:	maximum number of call graph entry (<number>)
		order:		call graph order (caller|callee)
		sort_key:	call graph sort key (function|address)
		branch:		include last branch info to call graph (branch)

		Default: fp,graph,0.5,caller,function

Requested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Chandler Carruth <chandlerc@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1445524112-5201-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 18 insertions, 6 deletions

diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
index aaf467c9ef2b..fce8161e54db 100644
--- a/tools/perf/util/callchain.h
+++ b/tools/perf/util/callchain.h
@@ -7,17 +7,29 @@
 #include "event.h"
 #include "symbol.h"
 
-#define CALLCHAIN_HELP "setup and enables call-graph (stack chain/backtrace) recording: "
+#define HELP_PAD "\t\t\t\t"
+
+#define CALLCHAIN_HELP "setup and enables call-graph (stack chain/backtrace):\n\n"
 
 #ifdef HAVE_DWARF_UNWIND_SUPPORT
-#define CALLCHAIN_RECORD_HELP  CALLCHAIN_HELP "fp dwarf lbr"
+# define RECORD_MODE_HELP  HELP_PAD "record_mode:\tcall graph recording mode (fp|dwarf|lbr)\n"
 #else
-#define CALLCHAIN_RECORD_HELP  CALLCHAIN_HELP "fp lbr"
+# define RECORD_MODE_HELP  HELP_PAD "record_mode:\tcall graph recording mode (fp|lbr)\n"
 #endif
 
-#define CALLCHAIN_REPORT_HELP  "output_type (graph, flat, fractal, or none), " \
-	"min percent threshold, optional print limit, callchain order, " \
-	"key (function or address), add branches"
+#define RECORD_SIZE_HELP						\
+	HELP_PAD "record_size:\tif record_mode is 'dwarf', max size of stack recording (<bytes>)\n" \
+	HELP_PAD "\t\tdefault: 8192 (bytes)\n"
+
+#define CALLCHAIN_RECORD_HELP  CALLCHAIN_HELP RECORD_MODE_HELP RECORD_SIZE_HELP
+
+#define CALLCHAIN_REPORT_HELP						\
+	HELP_PAD "print_type:\tcall graph printing style (graph|flat|fractal|none)\n" \
+	HELP_PAD "threshold:\tminimum call graph inclusion threshold (<percent>)\n" \
+	HELP_PAD "print_limit:\tmaximum number of call graph entry (<number>)\n" \
+	HELP_PAD "order:\t\tcall graph order (caller|callee)\n" \
+	HELP_PAD "sort_key:\tcall graph sort key (function|address)\n"	\
+	HELP_PAD "branch:\t\tinclude last branch info to call graph (branch)\n"
 
 enum perf_call_graph_mode {
 	CALLCHAIN_NONE,