[PATCH] prime_self_import: Assure no pending requests before object counting

[oscar.mateo@intel.com]

From: Oscar Mateo <oscar.mateo@intel.com>

We don't want a previously used object to be freed in the middle of a
before/after object counting operation (or we would get a "-1 objects
leaked" message). We have seen this happening, e.g., when a context
from a previous run dies, but its backing object is alive waiting for
a retire_work to kick in.

Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Cc: Ben Widawsky <ben@bwidawsk.net>
---
 tests/prime_self_import.c |   29 +++++++++++++++++++++++++++--
 1 file changed, 27 insertions(+), 2 deletions(-)

diff --git a/tests/prime_self_import.c b/tests/prime_self_import.c
index 481a809..e48abd1 100644
--- a/tests/prime_self_import.c
+++ b/tests/prime_self_import.c
@@ -211,6 +211,25 @@ static void test_with_one_bo(void)
 	check_bo(fd2, handle_import1, fd2, handle_import1);
 }
 
+static void retire_requests(void)
+{
+	char fname[FILENAME_MAX];
+	int drop_caches_fd;
+	const char *data = "0x4";
+
+	snprintf(fname, FILENAME_MAX, "%s/%i/%s",
+		 "/sys/kernel/debug/dri", drm_get_card(),
+		 "i915_gem_drop_caches");
+
+	drop_caches_fd = open(fname, O_WRONLY);
+
+	if (drop_caches_fd >= 0)
+	{
+		write(drop_caches_fd, data, strlen(data) + 1);
+		close(drop_caches_fd);
+	}
+}
+
 static int get_object_count(void)
 {
 	FILE *file;
@@ -252,10 +271,13 @@ static void test_reimport_close_race(void)
 	pthread_t *threads;
 	int r, i, num_threads;
 	int fds[2];
-	int obj_count = get_object_count();
+	int obj_count;
 	void *status;
 	uint32_t handle;
 
+	retire_requests();
+	obj_count = get_object_count();
+
 	num_threads = sysconf(_SC_NPROCESSORS_ONLN);
 
 	threads = calloc(num_threads, sizeof(pthread_t));
@@ -330,9 +352,12 @@ static void test_export_close_race(void)
 	pthread_t *threads;
 	int r, i, num_threads;
 	int fd;
-	int obj_count = get_object_count();
+	int obj_count;
 	void *status;
 
+	retire_requests();
+	obj_count = get_object_count();
+
 	num_threads = sysconf(_SC_NPROCESSORS_ONLN);
 
 	threads = calloc(num_threads, sizeof(pthread_t));
-- 
1.7.9.5