perf hists browser: Show message for percent limit

Like the stdio, it should show messages about omitted hierarchy entries.
Please refer the previous commit for more details.

As it needs to check an entry is omitted or not multiple times, add the
has_no_entry field in the hist entry.

Suggested-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1456488800-28124-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/ui/browsers/hists.c

@@ -260,6 +260,9 @@ static int hierarchy_count_rows(struct hist_browser *hb, struct hist_entry *he,
 	if (he->leaf)
 		return callchain__count_rows(&he->sorted_chain);
 
+	if (he->has_no_entry)
+		return 1;
+
 	node = rb_first(&he->hroot_out);
 	while (node) {
 		float percent;
@@ -409,10 +412,18 @@ static bool hist_browser__toggle_fold(struct hist_browser *browser)
 			/* account grand children */
 			if (symbol_conf.report_hierarchy)
 				browser->b.nr_entries += child_rows - he->nr_rows;
+
+			if (!he->leaf && he->nr_rows == 0) {
+				he->has_no_entry = true;
+				he->nr_rows = 1;
+			}
 		} else {
 			if (symbol_conf.report_hierarchy)
 				browser->b.nr_entries -= child_rows - he->nr_rows;
 
+			if (he->has_no_entry)
+				he->has_no_entry = false;
+
 			he->nr_rows = 0;
 		}
 
@@ -545,6 +556,12 @@ __hist_browser__set_folding(struct hist_browser *browser, bool unfold)
 			browser->nr_hierarchy_entries++;
 		if (he->leaf)
 			browser->nr_callchain_rows += he->nr_rows;
+		else if (unfold && !hist_entry__has_hierarchy_children(he, browser->min_pcnt)) {
+			browser->nr_hierarchy_entries++;
+			he->has_no_entry = true;
+			he->nr_rows = 1;
+		} else
+			he->has_no_entry = false;
 	}
 }
 
@@ -1412,6 +1429,75 @@ show_callchain:
 	return printed;
 }
 
+static int hist_browser__show_no_entry(struct hist_browser *browser,
+				       unsigned short row,
+				       int level, int nr_sort_keys)
+{
+	int width = browser->b.width;
+	bool current_entry = ui_browser__is_current_entry(&browser->b, row);
+	bool first = true;
+	int column = 0;
+	int ret;
+	struct perf_hpp_fmt *fmt;
+
+	if (current_entry) {
+		browser->he_selection = NULL;
+		browser->selection = NULL;
+	}
+
+	hist_browser__gotorc(browser, row, 0);
+
+	if (current_entry && browser->b.navkeypressed)
+		ui_browser__set_color(&browser->b, HE_COLORSET_SELECTED);
+	else
+		ui_browser__set_color(&browser->b, HE_COLORSET_NORMAL);
+
+	ui_browser__write_nstring(&browser->b, "", level * HIERARCHY_INDENT);
+	width -= level * HIERARCHY_INDENT;
+
+	hists__for_each_format(browser->hists, fmt) {
+		if (perf_hpp__should_skip(fmt, browser->hists) ||
+		    column++ < browser->b.horiz_scroll)
+			continue;
+
+		if (perf_hpp__is_sort_entry(fmt) ||
+		    perf_hpp__is_dynamic_entry(fmt))
+			break;
+
+		ret = fmt->width(fmt, NULL, hists_to_evsel(browser->hists));
+
+		if (first) {
+			/* for folded sign */
+			first = false;
+			ret++;
+		} else {
+			/* space between columns */
+			ret += 2;
+		}
+
+		ui_browser__write_nstring(&browser->b, "", ret);
+		width -= ret;
+	}
+
+	ui_browser__write_nstring(&browser->b, "", nr_sort_keys * HIERARCHY_INDENT);
+	width -= nr_sort_keys * HIERARCHY_INDENT;
+
+	if (column >= browser->b.horiz_scroll) {
+		char buf[32];
+
+		ret = snprintf(buf, sizeof(buf), "no entry >= %.2f%%", browser->min_pcnt);
+		ui_browser__printf(&browser->b, "  %s", buf);
+		width -= ret + 2;
+	}
+
+	/* The scroll bar isn't being used */
+	if (!browser->b.navkeypressed)
+		width += 1;
+
+	ui_browser__write_nstring(&browser->b, "", width);
+	return 1;
+}
+
 static int advance_hpp_check(struct perf_hpp *hpp, int inc)
 {
 	advance_hpp(hpp, inc);
@@ -1575,6 +1661,14 @@ static unsigned int hist_browser__refresh(struct ui_browser *browser)
 			row += hist_browser__show_hierarchy_entry(hb, h, row,
 								  h->depth,
 								  nr_sort);
+			if (row == browser->rows)
+				break;
+
+			if (h->has_no_entry) {
+				hist_browser__show_no_entry(hb, row, h->depth,
+							    nr_sort);
+				row++;
+			}
 		} else {
 			row += hist_browser__show_entry(hb, h, row);
 		}
@@ -2461,6 +2555,11 @@ static void hist_browser__update_percent_limit(struct hist_browser *hb,
 	while ((nd = hists__filter_entries(nd, hb->min_pcnt)) != NULL) {
 		he = rb_entry(nd, struct hist_entry, rb_node);
 
+		if (he->has_no_entry) {
+			he->has_no_entry = false;
+			he->nr_rows = 0;
+		}
+
 		if (!he->leaf || !symbol_conf.use_callchain)
 			goto next;
 

tools/perf/util/hist.c

@@ -1625,6 +1625,7 @@ static void hists__remove_entry_filter(struct hists *hists, struct hist_entry *h
 
 			/* force fold unfiltered entry for simplicity */
 			parent->unfolded = false;
+			parent->has_no_entry = false;
 			parent->row_offset = 0;
 			parent->nr_rows = 0;
 next:
@@ -1637,6 +1638,7 @@ next:
 
 	/* force fold unfiltered entry for simplicity */
 	h->unfolded = false;
+	h->has_no_entry = false;
 	h->row_offset = 0;
 	h->nr_rows = 0;
 

tools/perf/util/sort.h

@@ -117,6 +117,7 @@ struct hist_entry {
 			bool	init_have_children;
 			bool	unfolded;
 			bool	has_children;
+			bool	has_no_entry;
 		};
 	};
 	char			*srcline;