[i-g-t PATCH v3 2/2] tests/lib: make sure the GPU is idle at test start and exit

[Imre Deak <imre.deak@intel.com>]

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=64270

v2:
- Make sure also that the GPU is idle at start and error exit of any
  test using drm_open_any(). (Daniel)
v3:
- actually call gem_quiescent_gpu() at exit

Signed-off-by: Imre Deak <imre.deak@intel.com>
---
 lib/drmtest.c | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/lib/drmtest.c b/lib/drmtest.c
index 2d37fb6..d17dbb0 100644
--- a/lib/drmtest.c
+++ b/lib/drmtest.c
@@ -228,7 +228,7 @@ int drm_get_card(int master)
 }
 
 /** Open the first DRM device we can find, searching up to 16 device nodes */
-int drm_open_any(void)
+static int __drm_open_any(void)
 {
 	char *name;
 	int ret, fd;
@@ -248,6 +248,31 @@ int drm_open_any(void)
 	return fd;
 }
 
+static void quiescent_gpu_at_exit(int sig)
+{
+	int fd;
+
+	fd = __drm_open_any();
+	if (fd >= 0) {
+		gem_quiescent_gpu(fd);
+		close(fd);
+	}
+}
+
+int drm_open_any(void)
+{
+	static int open_count;
+	int fd = __drm_open_any();
+
+	if (fd < 0 || __sync_fetch_and_add(&open_count, 1))
+		return fd;
+
+	gem_quiescent_gpu(fd);
+	drmtest_install_exit_handler(quiescent_gpu_at_exit);
+
+	return fd;
+}
+
 /**
  * Open the first DRM device we can find where we end up being the master.
  */
-- 
1.8.1.2