drmtest: Install exithandler for i915, even in multidriver tests

If we opened the driver multiple times, we would not flush i915 if it
was opened second. The persistence of one test state into a second can
upset third parties, e.g. prime_vgem upsetting vgem_basic (due to
references from i915.ko to vgem.ko preventing module unload).

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

1 files changed, 10 insertions, 6 deletions

diff --git a/lib/drmtest.c b/lib/drmtest.c
index 40bbff6e..5d3aaa83 100644
--- a/lib/drmtest.c
+++ b/lib/drmtest.c
@@ -344,14 +344,18 @@ int drm_open_driver(int chipset)
 	fd = __drm_open_driver(chipset);
 	igt_skip_on_f(fd<0, "No known gpu found\n");
 
-	if (__sync_fetch_and_add(&open_count, 1))
-		return fd;
-
+	/* For i915, at least, we ensure that the driver is idle before
+	 * starting a test and we install an exit handler to wait until
+	 * idle before quitting.
+	 */
 	if (is_i915_device(fd)) {
-		gem_quiescent_gpu(fd);
-		igt_install_exit_handler(quiescent_gpu_at_exit);
+		if (__sync_fetch_and_add(&open_count, 1) == 0) {
+			gem_quiescent_gpu(fd);
+
+			at_exit_drm_fd = __drm_open_driver(chipset);
+			igt_install_exit_handler(quiescent_gpu_at_exit);
+		}
 	}
-	at_exit_drm_fd = __drm_open_driver(chipset);
 
 	return fd;
 }