[PATCH i-g-t] lib/igt_pm: Adjust pm status check timeout and log timing

[don.hiatt at intel.com]

From: Don Hiatt <don.hiatt at intel.com>

Increase the overall time we wait to achieve the desired runtime
status to 15 seconds to fix an occasional timeout and do so
in 1 second increments to speed up exiting. Also log the
amount of time we waited to get a handle on how much variation
we run into.

Signed-off-by: Don Hiatt <don.hiatt at intel.com>
---
 lib/igt_pm.c | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/lib/igt_pm.c b/lib/igt_pm.c
index 9d441e1b76ff..13675fca0c9d 100644
--- a/lib/igt_pm.c
+++ b/lib/igt_pm.c
@@ -747,8 +747,8 @@ static const char *_pm_status_name(enum igt_runtime_pm_status status)
  * igt_wait_for_pm_status:
  * @status: desired runtime PM status
  *
- * Waits until for the driver to switch to into the desired runtime PM status,
- * with a 10 second timeout.
+ * Waits for the driver to switch into the desired runtime PM status,
+ * with up to a 15 second timeout in 1 second increments.
  *
  * Returns:
  * True if the desired runtime PM status was attained, false if the operation
@@ -758,7 +758,7 @@ bool igt_wait_for_pm_status(enum igt_runtime_pm_status status)
 {
 	enum igt_runtime_pm_status expected = status;
 	bool ret;
-	int fd;
+	int fd, i;
 
 	if (__igt_pm_power < 0)
 		return false;
@@ -766,8 +766,16 @@ bool igt_wait_for_pm_status(enum igt_runtime_pm_status status)
 	fd = openat(__igt_pm_power, "runtime_status", O_RDONLY);
 	igt_assert_f(fd >= 0, "Can't open runtime_status\n");
 
-	ret = igt_wait((status = __igt_get_runtime_pm_status(fd)) == expected,
-		       10000, 100);
+	for (i=1; i < 16; ++i) {
+		ret = igt_wait((status = __igt_get_runtime_pm_status(fd)) == expected,
+				1000, 100);
+
+		if (ret) {
+			igt_info("Got expected (%s) runtime pm status in %d second(s)\n",
+				 _pm_status_name(expected), i);
+			break;
+		}
+	}
 	close(fd);
 
 	if (!ret)
-- 
2.25.0