intel-gpu-overlay: Move local perf implementation to a library

Idea is to avoid duplication across multiple users in
upcoming patches.

v2: Commit message and use a separate library instead of piggy-
    backing to libintel_tools. (Chris Wilson)

v3: Add Petri's meson build recipe.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Petri Latvala <petri.latvala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 26 insertions, 0 deletions

diff --git a/lib/igt_perf.c b/lib/igt_perf.c
new file mode 100644
index 00000000..45cccff0
--- /dev/null
+++ b/lib/igt_perf.c
@@ -0,0 +1,26 @@
+#include <stdint.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+
+#include "igt_perf.h"
+
+uint64_t i915_type_id(void)
+{
+	char buf[1024];
+	int fd, n;
+
+	fd = open("/sys/bus/event_source/devices/i915/type", 0);
+	if (fd < 0) {
+		n = -1;
+	} else {
+		n = read(fd, buf, sizeof(buf)-1);
+		close(fd);
+	}
+	if (n < 0)
+		return 0;
+
+	buf[n] = '\0';
+	return strtoull(buf, 0, 0);
+}
+