[PATCH i-g-t] tests/gem_ppgtt: Check for vm leaks with flink and ppgtt

Tvrtko Ursulin
2015-04-20T12:14:22Z

From: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Using imported objects should not leak i915 vmas (and vms).

In practice this simulates Xorg importing fbcon and leaking (or not) one vma
per Xorg startup cycle.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
---
tests/gem_ppgtt.c | 100 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 100 insertions(+)

diff --git a/tests/gem_ppgtt.c b/tests/gem_ppgtt.c
index 5bf773c..9b5b3ee 100644
--- a/tests/gem_ppgtt.c
+++ b/tests/gem_ppgtt.c
@@ -200,6 +200,103 @@ static void surfaces_check(dri_bo **bo, int count, uint32_t expected)
}
}

+static void flink_and_contexts(void)
+{
+ drm_intel_bufmgr *bufmgr;
+ int fd, fd2;
+ dri_bo *bo;
+ uint32_t flink_name;
+ unsigned int max_line = 0, num_lines = 0, cnt = 0;
+ int ret;
+
+ /*
+ * Export a bo via flink and access it from a child process via a
+ * different ppggtt context. Make sure when child exists that the vma
+ * (and hence the vm), associated with its ppgtt context, is torn down.
+ */
+
+ fd = drm_open_any();
+
+ bufmgr = drm_intel_bufmgr_gem_init(fd, 4096);
+ igt_assert(bufmgr);
+
+ bo = create_bo(bufmgr, 0);
+ igt_assert(bo);
+
+ ret = drm_intel_bo_flink(bo, &flink_name);
+ igt_assert(ret == 0);
+
+ igt_fork(child, 20) {
+ int devid;
+ drm_intel_bufmgr *bufmgr;
+ int fd;
+ dri_bo *bo, *import;
+ struct intel_batchbuffer *batch;
+
+ fd = drm_open_any();
+ devid = intel_get_drm_devid(fd);
+
+ bufmgr = drm_intel_bufmgr_gem_init(fd, 4096);
+ igt_assert(bufmgr);
+
+ bo = create_bo(bufmgr, 0);
+ import = drm_intel_bo_gem_create_from_name(bufmgr,
+ "flink_and_contexts",
+ flink_name);
+ igt_assert(bo && import);
+
+ batch = intel_batchbuffer_alloc(bufmgr, devid);
+ igt_assert(batch);
+
+ intel_copy_bo(batch, bo, import, SIZE);
+
+ intel_batchbuffer_free(batch);
+
+ dri_bo_unreference(import);
+ dri_bo_unreference(bo);
+
+ drm_intel_bufmgr_destroy(bufmgr);
+ close(fd);
+
+ exit(0);
+ }
+
+ igt_waitchildren();
+
+ /*
+ * Count the longest line in the file which lists the vmas per object.
+ * This might be a bit fragile so maybe there is a better way.
+ */
+ fd2 = open("/sys/kernel/debug/dri/0/i915_gem_gtt", O_RDONLY);
+ igt_assert(fd2 >= 0);
+
+ do {
+ char ch;
+
+ ret = read(fd2, &ch, 1);
+ if (ret == 0)
+ break;
+ igt_assert(ret == 1);
+ if (ch == '\n') {
+ if (cnt > max_line)
+ max_line = cnt;
+ num_lines++;
+ cnt = 0;
+ } else {
+ cnt++;
+ }
+ } while (true);
+
+ close(fd2);
+
+ dri_bo_unreference(bo);
+ drm_intel_bufmgr_destroy(bufmgr);
+ close(fd);
+
+ igt_assert(num_lines >= 1);
+ igt_assert(max_line < 1000);
+}
+
#define N_CHILD 8
int main(int argc, char **argv)
{
@@ -229,5 +326,8 @@ int main(int argc, char **argv)
surfaces_check(rcs, N_CHILD, 0x8000 / N_CHILD);
}

+ igt_subtest("flink-vs-ctx-vm-leak")
+ flink_and_contexts();
+
igt_exit();
}
--
2.3.5