trace-graph: Add labels when enough room permits

Add labels to the graph if there's enough room to show them.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 93 insertions, 0 deletions

diff --git a/trace-graph.c b/trace-graph.c
index b2ff3b2..1f5e4cf 100644
--- a/trace-graph.c
+++ b/trace-graph.c
@@ -654,17 +654,88 @@ static void set_color_by_pid(GtkWidget *widget, GdkGC *gc, gint pid)
         gdk_gc_set_foreground(gc, &color);
 }
 
+static void draw_event_label(struct graph_info *ginfo, gint cpu,
+                            gint event_id, gint pid,
+                            gint p1, gint p2, gint p3,
+                            gint width_16, PangoFontDescription *font)
+{
+        struct event *event;
+        PangoLayout *layout;
+        struct trace_seq s;
+        gint text_width;
+        gint text_height;
+        gint x, y;
+
+
+        /* No room to print */
+        if (((p3 - p2) < width_16 / 2 ||
+             (p2 - p1) < width_16 / 2))
+                return;
+
+        /* Check if we can show some data */
+
+        event = pevent_data_event_from_type(ginfo->pevent, event_id);
+
+        trace_seq_init(&s);
+        trace_seq_printf(&s, "%s-%d\n%s\n",
+                         pevent_data_comm_from_pid(ginfo->pevent, pid),
+                         pid, event->name);
+
+        layout = gtk_widget_create_pango_layout(ginfo->draw, s.buffer);
+        pango_layout_set_font_description(layout, font);
+
+        pango_layout_get_pixel_size(layout, &text_width, &text_height);
+
+        if ((p3 - p2) < text_width / 2 ||
+            (p2 - p1) < text_width / 2) {
+                g_object_unref(layout);
+                return;
+        }
+
+        x = p2 - text_width / 2;
+        y = (CPU_TOP(cpu) - text_height + 5);
+        gdk_draw_layout(ginfo->curr_pixmap, ginfo->draw->style->black_gc,
+                        x, y, layout);
+
+
+        gdk_draw_line(ginfo->curr_pixmap, ginfo->draw->style->black_gc,
+                      p2, CPU_TOP(cpu) - 5, p2, CPU_TOP(cpu) - 1);
+
+        g_object_unref(layout);
+}
+
 static void draw_cpu(struct graph_info *ginfo, gint cpu,
                      gint new_width)
 {
+        static PangoFontDescription *font;
+        PangoLayout *layout;
         gint height = CPU_MIDDLE(cpu);
         struct record *record;
         static GdkGC *gc;
+        static gint width_16;
         guint64 ts;
         gint last_pid = -1;
         gint last_x = 0;
         gint pid;
         gint x;
+        gint p1 = 0, p2 = 0, p3 = 0;
+        gint last_event_id = 0;
+        gint event_id;
+
+        /* Calculate the size of 16 characters */
+        if (!width_16) {
+                gchar buf[17];
+                gint text_height;
+
+                memset(buf, 'a', 16);
+                buf[16] = 0;
+
+                font = pango_font_description_from_string("Sans 8");
+                layout = gtk_widget_create_pango_layout(ginfo->draw, buf);
+                pango_layout_set_font_description(layout, font);
+                pango_layout_get_pixel_size(layout, &width_16, &text_height);
+                g_object_unref(layout);
+        }
 
         if (!gc)
                 gc = gdk_gc_new(ginfo->draw->window);
@@ -689,6 +760,8 @@ static void draw_cpu(struct graph_info *ginfo, gint cpu,
                 if (!check_sched_switch(ginfo, record, &pid, NULL))
                         pid = pevent_data_pid(ginfo->pevent, record);
 
+                event_id = pevent_data_type(ginfo->pevent, record);
+
                 if (last_pid != pid) {
 
                         if (last_pid < 0)
@@ -711,9 +784,29 @@ static void draw_cpu(struct graph_info *ginfo, gint cpu,
 
                 gdk_draw_line(ginfo->curr_pixmap, gc, // ginfo->draw->style->black_gc,
                               x, CPU_TOP(cpu), x, CPU_BOTTOM(cpu));
+
+                /* Figure out if we can show the text for the previous record */
+
+                p3 = x;
+
+                /* Make sure p2 will be non-zero the next iteration */
+                if (!p3)
+                        p3 = 1;
+
+                /* first record, continue */
+                if (p2)
+                        draw_event_label(ginfo, cpu, last_event_id, last_pid,
+                                         p1, p2, p3, width_16, font);
+
+                p1 = p2;
+                p2 = p3;
+                last_event_id = event_id;
                 free(record);
         }
 
+        draw_event_label(ginfo, cpu, last_event_id, last_pid,
+                         p1, p2, ginfo->draw_width, width_16, font);
+
 
         if (last_pid > 0) {
                 x = ginfo->draw_width;