perf ui browser: Move the extra title lines from the hists browser

This will be useful for the annotate browser as well, that wants to have
extra title lines, i.e. the current ui_browser unconditionally reserves
the first line for a browser title and the last one for status messages.

But some browsers, like the buckets one (hists browser) needs extra
lines to show headers, allowing it to be shown or not, press 'H' in
'perf top' or 'perf report' to see this feature.

So move that logic to the core ui_browser used by the hists_browser
('perf top' and 'perf report' main interface) so that it can be used by
the annotate browser too.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Martin Liška <mliska@suse.cz>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196935
Link: https://lkml.kernel.org/n/tip-r38xm3ut37ulbg1o5tn5iise@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/ui/browser.c

@@ -45,11 +45,16 @@ void ui_browser__set_percent_color(struct ui_browser *browser,
 	 ui_browser__set_color(browser, color);
 }
 
-void ui_browser__gotorc(struct ui_browser *browser, int y, int x)
+void ui_browser__gotorc_title(struct ui_browser *browser, int y, int x)
 {
 	SLsmg_gotorc(browser->y + y, browser->x + x);
 }
 
+void ui_browser__gotorc(struct ui_browser *browser, int y, int x)
+{
+	SLsmg_gotorc(browser->y + y + browser->extra_title_lines, browser->x + x);
+}
+
 void ui_browser__write_nstring(struct ui_browser *browser __maybe_unused, const char *msg,
 			       unsigned int width)
 {
@@ -191,6 +196,7 @@ void ui_browser__refresh_dimensions(struct ui_browser *browser)
 {
 	browser->width = SLtt_Screen_Cols - 1;
 	browser->height = browser->rows = SLtt_Screen_Rows - 2;
+	browser->rows -= browser->extra_title_lines;
 	browser->y = 1;
 	browser->x = 0;
 }

tools/perf/ui/browser.h

@@ -17,6 +17,7 @@ struct ui_browser {
 	u64	      index, top_idx;
 	void	      *top, *entries;
 	u16	      y, x, width, height, rows, columns, horiz_scroll;
+	u8	      extra_title_lines;
 	int	      current_color;
 	void	      *priv;
 	const char    *title;
@@ -38,6 +39,7 @@ bool ui_browser__is_current_entry(struct ui_browser *browser, unsigned row);
 void ui_browser__refresh_dimensions(struct ui_browser *browser);
 void ui_browser__reset_index(struct ui_browser *browser);
 
+void ui_browser__gotorc_title(struct ui_browser *browser, int y, int x);
 void ui_browser__gotorc(struct ui_browser *browser, int y, int x);
 void ui_browser__write_nstring(struct ui_browser *browser, const char *msg,
 			       unsigned int width);

tools/perf/ui/browsers/hists.c

@@ -61,6 +61,15 @@ static int hist_browser__get_folding(struct hist_browser *browser)
 	return unfolded_rows;
 }
 
+static void hist_browser__set_title_space(struct hist_browser *hb)
+{
+	struct ui_browser *browser = &hb->b;
+	struct hists *hists = hb->hists;
+	struct perf_hpp_list *hpp_list = hists->hpp_list;
+
+	browser->extra_title_lines = hb->show_headers ? hpp_list->nr_header_lines : 0;
+}
+
 static u32 hist_browser__nr_entries(struct hist_browser *hb)
 {
 	u32 nr_entries;
@@ -81,10 +90,16 @@ static void hist_browser__update_rows(struct hist_browser *hb)
 	struct ui_browser *browser = &hb->b;
 	struct hists *hists = hb->hists;
 	struct perf_hpp_list *hpp_list = hists->hpp_list;
-	u16 header_offset, index_row;
+	u16 index_row;
+
+	if (!hb->show_headers) {
+		browser->rows += browser->extra_title_lines;
+		browser->extra_title_lines = 0;
+		return;
+	}
 
-	header_offset = hb->show_headers ? hpp_list->nr_header_lines : 0;
-	browser->rows = browser->height - header_offset;
+	browser->extra_title_lines = hpp_list->nr_header_lines;
+	browser->rows -= browser->extra_title_lines;
 	/*
 	 * Verify if we were at the last line and that line isn't
 	 * visibe because we now show the header line(s).
@@ -107,17 +122,6 @@ static void hist_browser__refresh_dimensions(struct ui_browser *browser)
  	 *	  changeset.
  	 */
 	ui_browser__refresh_dimensions(browser);
-	hist_browser__update_rows(hb);
-}
-
-static void hist_browser__gotorc(struct hist_browser *browser, int row, int column)
-{
-	struct hists *hists = browser->hists;
-	struct perf_hpp_list *hpp_list = hists->hpp_list;
-	u16 header_offset;
-
-	header_offset = browser->show_headers ? hpp_list->nr_header_lines : 0;
-	ui_browser__gotorc(&browser->b, row + header_offset, column);
 }
 
 static void hist_browser__reset(struct hist_browser *browser)
@@ -732,7 +736,7 @@ static void hist_browser__show_callchain_entry(struct hist_browser *browser,
 	}
 
 	ui_browser__set_color(&browser->b, color);
-	hist_browser__gotorc(browser, row, 0);
+	ui_browser__gotorc(&browser->b, row, 0);
 	ui_browser__write_nstring(&browser->b, " ", offset);
 	ui_browser__printf(&browser->b, "%c", folded_sign);
 	ui_browser__write_graph(&browser->b, show_annotated ? SLSMG_RARROW_CHAR : ' ');
@@ -1248,7 +1252,7 @@ static int hist_browser__show_entry(struct hist_browser *browser,
 		};
 		int column = 0;
 
-		hist_browser__gotorc(browser, row, 0);
+		ui_browser__gotorc(&browser->b, row, 0);
 
 		hists__for_each_format(browser->hists, fmt) {
 			char s[2048];
@@ -1357,7 +1361,7 @@ static int hist_browser__show_hierarchy_entry(struct hist_browser *browser,
 		goto show_callchain;
 	}
 
-	hist_browser__gotorc(browser, row, 0);
+	ui_browser__gotorc(&browser->b, row, 0);
 
 	if (current_entry && browser->b.navkeypressed)
 		ui_browser__set_color(&browser->b, HE_COLORSET_SELECTED);
@@ -1506,7 +1510,7 @@ static int hist_browser__show_no_entry(struct hist_browser *browser,
 		browser->selection = NULL;
 	}
 
-	hist_browser__gotorc(browser, row, 0);
+	ui_browser__gotorc(&browser->b, row, 0);
 
 	if (current_entry && browser->b.navkeypressed)
 		ui_browser__set_color(&browser->b, HE_COLORSET_SELECTED);
@@ -1712,7 +1716,7 @@ static void hists_browser__headers(struct hist_browser *browser)
 		hists_browser__scnprintf_headers(browser, headers,
 						 sizeof(headers), line);
 
-		ui_browser__gotorc(&browser->b, line, 0);
+		ui_browser__gotorc_title(&browser->b, line, 0);
 		ui_browser__set_color(&browser->b, HE_COLORSET_ROOT);
 		ui_browser__write_nstring(&browser->b, headers, browser->b.width + 1);
 	}
@@ -2142,6 +2146,7 @@ void hist_browser__init(struct hist_browser *browser,
 	browser->b.seek			= ui_browser__hists_seek;
 	browser->b.use_navkeypressed	= true;
 	browser->show_headers		= symbol_conf.show_hist_headers;
+	hist_browser__set_title_space(browser);
 
 	if (symbol_conf.report_hierarchy) {
 		struct perf_hpp_list_node *fmt_node;