overlay: Auatomatically mount debugfs

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

overlay/Makefile.am

@@ -14,6 +14,8 @@ intel_gpu_overlay_SOURCES = \
 	chart.c \
 	cpu-top.h \
 	cpu-top.c \
+	debugfs.h \
+	debugfs.c \
 	gem-objects.h \
 	gem-objects.c \
 	gpu-top.h \

overlay/debugfs.c

@@ -0,0 +1,21 @@
+#include <sys/stat.h>
+#include <sys/mount.h>
+#include <errno.h>
+
+#include "debugfs.h"
+
+int debugfs_init(void)
+{
+	struct stat st;
+
+	if (stat("/sys/kernel/debug/dri", &st) == 0)
+		return 0;
+
+	if (stat("/sys/kernel/debug", &st))
+		return errno;
+
+	if (mount("debug", "/sys/kernel/debug", "debugfs", 0, 0))
+		return errno;
+
+	return 0;
+}

overlay/debugfs.h

@@ -0,0 +1 @@
+int debugfs_init(void);

overlay/overlay.c

@@ -517,6 +517,8 @@ int main(int argc, char **argv)
 	if (ctx.surface == NULL)
 		return ENOMEM;
 
+	debugfs_init();
+
 	init_gpu_top(&ctx, &ctx.gpu_top);
 	init_gpu_perf(&ctx, &ctx.gpu_perf);
 	init_gpu_freq(&ctx, &ctx.gpu_freq);