perf report: Add callchain value option

Now -g/--call-graph option supports how to display callchain values.
Possible values are 'percent', 'period' and 'count'.  The percent is
same as before and it's the default behavior.  The period displays the
raw period value rather than the percentage.  The count displays the
number of occurrences.

  $ perf report --no-children --stdio -g percent
  ...
    39.93%  swapper  [kernel.vmlinux]  [k] intel_idel
            |
            ---intel_idle
               cpuidle_enter_state
               cpuidle_enter
               call_cpuidle
               cpu_startup_entry
               |
               |--28.63%-- start_secondary
               |
                --11.30%-- rest_init

  $ perf report --no-children --show-total-period --stdio -g period
  ...
    39.93%   13018705  swapper  [kernel.vmlinux]  [k] intel_idel
            |
            ---intel_idle
               cpuidle_enter_state
               cpuidle_enter
               call_cpuidle
               cpu_startup_entry
               |
               |--9334403-- start_secondary
               |
                --3684302-- rest_init

  $ perf report --no-children --show-nr-samples --stdio -g count
  ...
    39.93%     80  swapper  [kernel.vmlinux]  [k] intel_idel
            |
            ---intel_idle
               cpuidle_enter_state
               cpuidle_enter
               call_cpuidle
               cpu_startup_entry
               |
               |--57-- start_secondary
               |
                --23-- rest_init

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1447047946-1691-6-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/ui/stdio/hist.c b/tools/perf/ui/stdio/hist.c
index f4de055..7ebc661 100644
--- a/tools/perf/ui/stdio/hist.c
+++ b/tools/perf/ui/stdio/hist.c
@@ -81,13 +81,14 @@
 					 int depth_mask, int left_margin)
 {
 	struct rb_node *node, *next;
-	struct callchain_node *child;
+	struct callchain_node *child = NULL;
 	struct callchain_list *chain;
 	int new_depth_mask = depth_mask;
 	u64 remaining;
 	size_t ret = 0;
 	int i;
 	uint entries_printed = 0;
+	int cumul_count = 0;
 
 	remaining = total_samples;
 
@@ -99,6 +100,7 @@
 		child = rb_entry(node, struct callchain_node, rb_node);
 		cumul = callchain_cumul_hits(child);
 		remaining -= cumul;
+		cumul_count += callchain_cumul_counts(child);
 
 		/*
 		 * The depth mask manages the output of pipes that show
@@ -148,6 +150,12 @@
 		if (!rem_sq_bracket)
 			return ret;
 
+		if (callchain_param.value == CCVAL_COUNT && child && child->parent) {
+			rem_node.count = child->parent->children_count - cumul_count;
+			if (rem_node.count <= 0)
+				return ret;
+		}
+
 		new_depth_mask &= ~(1 << (depth - 1));
 		ret += ipchain__fprintf_graph(fp, &rem_node, &rem_hits, depth,
 					      new_depth_mask, 0, total_samples,