perf timechart: Add a power-only mode

For doing work on the Linux power management components, I need to
make long (30+ seconds) traces. Currently, this then results in a
HUGE svg file, with mostly process data that isn't interesting.

This patch adds a --power-only mode to perf timechart that only
outputs the CPU power section of the SVG; this significantly
reduces the size of the SVG file, making even 30+ second traces
viewable with inkscape.

As a minor tweak for the same effect, the minimum text size is
decreased; current inkscape cannot zoom in deep enough to show text
this small, but it reduces inkscape compute time.
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Cc: peterz@infradead.org
LKML-Reference: <20090924154013.0675ab71@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

tools/perf/Documentation/perf-timechart.txt

@@ -31,6 +31,9 @@ OPTIONS
 -w::
 --width=::
         Select the width of the SVG file (default: 1000)
+-p::
+--power-only::
+        Only output the CPU power section of the diagram
 
 
 SEE ALSO

tools/perf/builtin-timechart.c

@@ -46,6 +46,8 @@ static u64		turbo_frequency;
 
 static u64		first_time, last_time;
 
+static int		power_only;
+
 
 static struct perf_header	*header;
 
@@ -547,7 +549,7 @@ static void end_sample_processing(void)
 	u64 cpu;
 	struct power_event *pwr;
 
-	for (cpu = 0; cpu < numcpus; cpu++) {
+	for (cpu = 0; cpu <= numcpus; cpu++) {
 		pwr = malloc(sizeof(struct power_event));
 		if (!pwr)
 			return;
@@ -871,7 +873,7 @@ static int determine_display_tasks(u64 threshold)
 		/* no exit marker, task kept running to the end */
 		if (p->end_time == 0)
 			p->end_time = last_time;
-		if (p->total_time >= threshold)
+		if (p->total_time >= threshold && !power_only)
 			p->display = 1;
 
 		c = p->all;
@@ -882,7 +884,7 @@ static int determine_display_tasks(u64 threshold)
 			if (c->start_time == 1)
 				c->start_time = first_time;
 
-			if (c->total_time >= threshold) {
+			if (c->total_time >= threshold && !power_only) {
 				c->display = 1;
 				count++;
 			}
@@ -1134,6 +1136,8 @@ static const struct option options[] = {
 		    "output file name"),
 	OPT_INTEGER('w', "width", &svg_page_width,
 		    "page width"),
+	OPT_BOOLEAN('p', "power-only", &power_only,
+		    "output power data only"),
 	OPT_END()
 };
 

tools/perf/util/svghelper.c

@@ -28,7 +28,7 @@ static u64 turbo_frequency, max_freq;
 
 int svg_page_width = 1000;
 
-#define MIN_TEXT_SIZE 0.001
+#define MIN_TEXT_SIZE 0.01
 
 static u64 total_height;
 static FILE *svgfile;
@@ -217,6 +217,18 @@ static char *cpu_model(void)
 		}
 		fclose(file);
 	}
+
+	/* CPU type */
+	file = fopen("/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies", "r");
+	if (file) {
+		while (fgets(buf, 255, file)) {
+			unsigned int freq;
+			freq = strtoull(buf, NULL, 10);
+			if (freq > max_freq)
+				max_freq = freq;
+		}
+		fclose(file);
+	}
 	return cpu_m;
 }