perf top: Add --percent-limit option

The --percent-limit option is for not showing small overhead entries in
the output.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1368497347-9628-8-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 19fe25f..f036af9b 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -296,7 +296,8 @@
 				     top->print_entries - printed);
 	putchar('\n');
 	hists__fprintf(&top->sym_evsel->hists, false,
-		       top->print_entries - printed, win_width, 0, stdout);
+		       top->print_entries - printed, win_width,
+		       top->min_percent, stdout);
 }
 
 static void prompt_integer(int *target, const char *msg)
@@ -580,7 +581,7 @@
 	list_for_each_entry(pos, &top->evlist->entries, node)
 		pos->hists.uid_filter_str = top->record_opts.target.uid_str;
 
-	perf_evlist__tui_browse_hists(top->evlist, help, &hbt, 0,
+	perf_evlist__tui_browse_hists(top->evlist, help, &hbt, top->min_percent,
 				      &top->session->header.env);
 
 	done = 1;
@@ -1021,6 +1022,16 @@
 	return record_parse_callchain_opt(opt, arg, unset);
 }
 
+static int
+parse_percent_limit(const struct option *opt, const char *arg,
+		    int unset __maybe_unused)
+{
+	struct perf_top *top = opt->value;
+
+	top->min_percent = strtof(arg, NULL);
+	return 0;
+}
+
 int cmd_top(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	int status;
@@ -1106,6 +1117,8 @@
 	OPT_STRING('M', "disassembler-style", &disassembler_style, "disassembler style",
 		   "Specify disassembler style (e.g. -M intel for intel syntax)"),
 	OPT_STRING('u', "uid", &target->uid_str, "user", "user to profile"),
+	OPT_CALLBACK(0, "percent-limit", &top, "percent",
+		     "Don't show entries under that percent", parse_percent_limit),
 	OPT_END()
 	};
 	const char * const top_usage[] = {